


consume the souvenirs

by sugarboat



Series: The Harbor is Yours [2]
Category: The Magnus Archives (Podcast)
Genre: Alternate Universe - Merpeople, Body Horror, Jon's a siren for Reasons, Knotting, M/M, Non-Human Genitalia, Other, Penetrative Sex, Sexual Coercion, but like reverse knotting, gendered sexualizing language, misuse of avatar powers
Language: English
Status: Completed
Published: 2021-02-05
Updated: 2021-02-05
Packaged: 2021-03-16 18:20:24
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,954
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29211810
Author URL: https://archiveofourown.org/users/sugarboat/pseuds/sugarboat
Summary: Peter plays with Elias' pet.
Relationships: Elias Bouchard/Jonathan "Jon" Sims | The Archivist, Elias Bouchard/Peter Lukas, Peter Lukas/Jonathan "Jon" Sims | The Archivist
Series: The Harbor is Yours [2]
Series URL: https://archiveofourown.org/series/2144715
Comments: 7
Kudos: 93





	consume the souvenirs

**Author's Note:**

> Not technically written for jonpeter week but posted in the spirit of jonpeter week. Takes place in an ambiguous future in this AU when Jon's been thoroughly trained and stockholmed.

The process of Jon shedding his scales so to speak is, quite frankly, disgusting. The inhuman pieces of him slough off like so much dead skin – leaves little curls of his fins behind like discarded scraps of satin. His tail buckles inwards like a quick-motion time lapse of a decaying corpse, and Peter doesn’t even begin to pretend he understands the why’s or how’s of the whole thing. He would almost say it isn’t worth it, except-

Except for how Peter gets to watch Jon writhe and gasp during it. Seems that for however awful the whole affair is from the outside, living through it is much worse. Jon claws at the ground, as if he’s trying to crawl away from the sensory input of his own body. He makes these wounded little noises that whimper in his throat, rolls his spine and hips like he’s shucking off a second skin. 

And, of course, there is the end result. 

Jon pulls himself up on new, trembling legs. All pale and unblemished skin slicked with gore. He’s flushed with exertion, sweat damp and fever-bright eyes. His hair is tousled from how he’d thrown himself around, and as Peter watches a tremor quivers through his whole body, threatens to buckle in his legs.

Peter can’t help himself. He lets out a low whistle and gives a little clap, grinning from ear to ear as the siren turns towards him with a pouty snarl on his face. 

“That was well done, wasn’t it? Quite the show you put on for us,” Peter says. 

The siren rounds on him. “Why don’t you just-”

Whatever Jon supposes he should do instead is left a pleasant mystery, as the siren’s knees give out entirely and Peter has to dip forward to catch the poor thing before it bashes its pretty face into the floor. 

“Careful, darling – you’re looking a touch weak in the knees. Just imagine what would have happened if I hadn’t been here.” 

“If only,” Jon drawls, and apparently, they’re just going to ignore how he’s clinging to Peter’s shoulders. How his attempts to straighten himself back up keep ending in shaking limbs and aborted motion. “Shouldn’t you be off somewhere? Alone?” 

The siren’s questions are still- unpleasant. Like someone’s scraping steel wool over his flesh, feeding it to him, scratching up his lips and his tongue and stripping skin all the way down his throat to where it settles, a hard and heavy weight, in his stomach and unravels to wrap around the answers it wants and pull them all right back out. 

Like that, but lessened in this form. An echo of itself, a ripple on the far edge of the water’s disturbance, liable to slip back into the water’s still form at any moment. Jon doesn’t have the power to demand answers from Peter now – truthfully, even at his best couldn’t wrangle more than a half-choked response out of him, so used to dealing with humans that split their insides with all the eagerness of an overripe fruit – but it does none of them any good to let poor habits go uncorrected. 

Peter lets go, and enjoys how the siren throws himself forward, clutches at him. The Forsaken world is close and Peter breathes in the heavy, wet fog that rolls in slowly to coat their forms. Thick enough to join the beads of salt water still dew-dropped on the siren’s skin, to swell them until they trickle down like streaks of rain. 

“If you wanted to be alone with me, Jon, you only had to say so,” Peter murmurs. Jon’s still holding onto him but he startles like he’s forgotten there’s anyone there. The Lonely has that effect on people. 

“I don’t,” Jon says, the words a white puff of breath in the air, stirring against Peter’s neck. 

“Well. I take you’d rather I left you to it, then-”

“No!” The siren’s fingers curl, like it still had the claws needed to dig into his skin. “Don’t- Don’t go, don’t _leave_ me here.”

“Now, now, Jon. You’ve made it fairly clear that you don’t want my company. Some people might take offense to that, but, I understand what that’s like. And I’d hate to overstay my welcome.” 

“I-” Jon presses himself forward, until his cheek is against Peter’s shoulder, nearly nuzzled against the crook of his neck. “Please, Peter.” 

“Oh, I don’t know if I’m convinced just yet,” Peter says, but he bends briefly to haul the siren up against him, hooks his hands beneath Jon’s thighs and encourages them wider as he takes his weight. His fingers threaten to slip in the slick blood and viscera still coating Jon’s legs. 

Jon has, predictably, not handled this repositioning well, yelping and twining his arms around Peter’s neck. “I suppose it’s too much to hope that you’ll just _tell_ me what will convince you.” 

“I may have had an idea or two,” Peter murmurs. He shifts the siren up a little higher, partially to get a better grip on the slippery little thing and mostly to enjoy how its entire body shivers in response to being tossed around a bit. He can feel the warmth of its flush. 

Jon gives a lengthy, heartfelt sigh that Peter chuckles at. Then there’s a hand tangled in his hair, clenching fingers and twisting motion that all, quite frankly, catch Peter by surprise. A forceful yank that has him tilting his head in response, a quick moment of his pulse pounding, the teasing burn in his scalp and tight pinpricks of pain. 

“Something like this, I assume.” Jon’s mouth hovers over his own, cool, cool breath at his lips. There’s the barest brush of contact that seems to narrow his perception to just these points of them. His voice is low, and nearly bored, and Christ if that doesn’t make Peter’s cock kick in his trousers. 

Well. He’s not about to be bested by a damn fish. 

“Something like that,” Peter repeats before maneuvering them so he can settle heavily onto Elias’ couch, turn his armful of siren into a lapful of the same. His prick is pressing up hard against his slacks and he pulls Jon down hard by his hips, grinding against that cute little slit he really needs to properly explore when all’s said and done. “Show me how badly you want me to stay.” 

His hips are rocking almost of their own accord, and Jon rolls his own readily enough for all the protests he otherwise gives. But if the siren wants to take charge Peter’s willing to let it, and he releases Jon to drape his arms along the back of the couch, gesturing for Jon to continue. 

“Go ahead,” he encourages. 

Jon scowls at him, all huffy and unmoving for just long enough for the Lonely’s fog to creep back in between them. Then there are hands fumbling with his belt, yanking at the buttons and zip of his trousers in a way that could almost be misinterpreted as overeager. Jon slows when he reaches the soft of his pants, fingers a tease as they trace the outline of his cock. 

“Don’t act like you don’t know what to do with it,” Peter chides. He reaches down to shuffle himself free all the same, wrapping his hand around Jon’s to take his prick in hand. His free hand anchors on the side of Jon’s hip, holds him steady. 

Jon’s lips purse. He gives Peter an offended little glare but then his head tilts to one side and his hand is moving along his cock like he’s getting himself familiar with every inch of it. Like Jon’s not been made intimately familiar with the entirety of it on multiple occasions, although Peter supposes Jon hasn’t been given much of an opportunity to do more than flail his pretty tail and get thoroughly fucked in the past. 

“Well?” Peter asks when Jon seems content to teasing stroke him, over and over, fingers deft and exploratory. 

Peter takes himself in hand and guides his cock towards Jon, slips the leaking head of prick along the strange lips of the- cunt, he supposes, the siren comes equipped with. It’s pretty and inhuman, anatomy subtly wrong but it parts against the pressure of his cock all the same, wet and warm as he slides up and down. There’s a fluttery little hole in there that causes Jon’s hips to buck when Peter plays at penetration, another slit further back that refuses to part for entrance. 

“Well, what?” Jon snaps. Peter keeps teasing him – both of them, really, pushing his hips up so his cock slips deeper and then withdraws, slips deeper still and pulls away again. “Believe me, your human- genitalia, are not nearly so fascinating as you might-”

Jon gasps as Peter lines up and hilts himself in a long, smooth glide, snatching Jon’s hand out of the way and pulling him down by his hips until Peter’s balls deep. The siren is as sinfully tight as ever, owing at least partially to some strange morphologic difference in their biologies. Muscles slick and clenching quiver around his cock, milk it in a rhythmic, peristaltic motion that has Peter tossing his head back, hissing and trying to fucking keep it together. 

“Do- Do you mind?” Jon bitches, his flushed cheeks and lidded eyes betraying how he’s not nearly so unaffected as he plays at. 

“I do, actually,” Peter replies when he can breathe again. When he thinks he can handle some kind of motion without blowing his load. He slaps the side of Jon’s ass – and quite an ass it is, whatever muscles have transfigured into these are certainly getting a regular workout – and bounces the siren a bit in his lap. “You’ve got two legs, let’s see you put them to work.” 

That pissy little look Jon gets probably isn’t intended to be anywhere as arousing as Peter finds it. Jon doesn’t know what he’s doing which, well, is fair at least. He lifts himself halfway up on tremulous thighs and Peter stifles a frankly undignified sound at the feeling. Pulling out of the siren is always harder than getting his dick inside it, like it’s just not made for the kind of fucking humans get up to. Every inch of that soft, wet cunt is clinging to his cock, grasping at it like wants to keep him balls deep the rest of the night. 

Jon settles his hands onto Peter’s shoulders, gives himself leverage. His head’s titled down in concentration, so when he glances back up to Peter it’s through the dark of his lashes. Peter wraps both his hands around Jon’s hips. 

“Keep going,” he encourages. Guides the siren up until that clingy little cunt is just barely held open by his prick and then pressuring Jon to lower himself back down. “Try to give a bit more effort, won’t you? I don’t think it’s too much to ask for some enthusiasm here, Jon. You’re meant to be showing me some desperation.” 

“I am so des-desperate,” Jon says. Going for, no doubt, dry, sarcastic, mouthy. Giving instead something else as he stutters from taking Peter’s cock again, breath hitching. 

“And what are you so desperate for?” Peter asks. He’ll die of blue balls if they keep this pace up, Jon working himself slowly in his lap. There’s no clit for him to play with, to get the siren properly wound up – there’s a cock, somewhere, he knows, with no actual idea what makes the thing come out except for fucking Jon until he cries. 

“You, Peter.” Even just with this slow, aching penetration Jon’s getting flushed down to his chest. Peter bucks up into him, groans at the slick spasm around his dick. Jon gasps and claws at his shoulders.

“’Course you are,” Peter manages between breaths. Working to help the siren, tugging him down hard into his lap, working him back up at more than a glacial pace. “You’re a proper little slut once you’ve gotten a cock inside you.” 

Jon doesn’t reply, but Peter attributes it to distraction rather than the siren actually disagreeing with him. Peter tilts Jon’s hips this way and that until the siren gives a ragged moan on the next downward bounce and his insides practically clamp down around Peter’s prick.

“Fuck,” Jon says, almost a moan. His hips twitch downward, little aborted movements that become full fledged grinding when Peter bucks his own up. 

He’s fairly certain he couldn’t get his cock out of the siren even if he wanted to right now. Those peristaltic motions that have never really let up are particularly noticeable now, rhythmic flexing and suckling along his cock, starting at the base where he’s buried to the balls in the siren’s slick cunt and pulling upwards, up, and up, clenching muscles trying to drag him impossibly deeper. Peter humps up helplessly into that feverish warmth, velvet soft tissue. 

“Christ.” Peter can’t get anything more intelligent out. He tugs Jon closer so he can sink his teeth into the side of the siren’s neck, a desperate attempt to ground himself in something, something outside of - _hot, tight, needy, hungry_ \- his dick. 

He feels precariously close already. Every muscle pulled taut, balls drawn up tight and Peter feels his dick twitch and leak at the thought of emptying them sheathed so deep in his pet. It’s almost equally dismaying and relieving when those muscles let up, go fluttery and quivering and finally, fucking finally, relax enough for movement. Peter hisses as he draws out. Jon whimpers, mouth dropped open so he can pant like the cock-hungry creature he is. 

“Going to tell me again about how desperate you are?” Peter asks. He pulls out entirely, ignoring how he wants nothing more than to sink back inside the siren. Instead teases at Jon’s fucked open hole, slipping his cock in and out in a shallow little fuck. Jon’s hips stutter down to meet him each and every time. 

“P-Please,” Jon breathes. “Peter-”

“Hmm.” Peter slips his fist up along his cock to stroke between Jon’s lips with his fingertips. “I don’t know, darling. It’s hard to tell if you’re being sincere.” 

Jon pins him with a look that’s somewhere between pouty and irritated. Peter traces where Jon’s pretty slit is stretched wide around his cock, probes and threatens to work his finger in alongside the thick head of his dick. It’s hard to say if Jon likes the idea or not – there’s a marked difference in the squirming of his hips, a subtle stiffening and flinch – but really that’s the best part about the siren: it doesn’t actually matter what he _wants_ , he always ends up letting Peter have his way. 

For a moment Peter imagines tossing the siren off his lap entirely. Holding it down and shoving his fist in that tight, clutching cunt of its. Grinding his knuckles into that spot inside it that makes its muscles clamp and spasm. How many times could he make it clench and release? Demand orgasms out of Jon until he goes limp and pliant, the clasp of his cunt reduced to weak, gentle fluttering. 

Well. Peter doesn’t actually know if the thing has come or not. He assumes Jon has. He certainly doesn’t blame for the siren coming around his cock like a good little slut. 

“Are you going to do something?” Jon demands. Gasps when Peter shifts his fingers to pinch the lip of his slit- gasps and circles in his hips in a short downward buck. “Or am I just meant to be decorating your lap for the rest of the evening?” 

“Well doesn’t that sound delightful.” He pinches his fingers together again, Jon’s delicate flesh still captured. Twists them a bit, digs his thumbnail in, to watch Jon flush and twitch into the sensation. “Would you like that darling?” 

Something pangs between, around them, fractaled in the fog like light being caught and refracted. Difficult to say which of them it echoes off of first, when Jon glances to the side where they both know Elias must be, swathed from his sight as they are. It’s the kind of dull hurt the Forsaken is built from – neither of them the other’s first choice. 

For some reason it makes Jon dip in closer. The siren’s hands slide from Peter’s shoulders, to drape his arms over and around instead. Their lips brush and it’s almost unbearable, makes Peter want to sink into the distant sounds of a coastline, cold and out of reach. 

Jon smirks against his mouth. It sends a hot surge jolting through Peter, anger and arousal pooling dangerously, headily together, and if he hadn’t already liked that mix he’d never have gotten involved with Elias in the first place. He puts his hands back on Jon’s hips and jerks the siren down, fucking his hips up at the same time so his cock rams inside the siren’s slick cunt, drills that deep spot that sends it breathless and clenching and rides out the wave of tight, almost suckling heat spasming around his length. 

Jon’s body only just begins to ease when Peter forces him back up – laborious as the action is, and Christ, it shouldn’t be such an arousing thought, that the siren’s body itself doesn’t want to give up his cock. Jon tries to stutter something but Peter ignores it in favor of tugging him back down, snapping his hips to meet him. 

It’s so hard to think anything around how good it feels, all that rhythmic, rippling muscle milking his cock, tight walls fluttering against his prick. Peter drops his forehead against Jon’s collar. His hips keep bucking like he could go anywhere, get any deeper, grinding desperately. Jon is making quiet noises, hands scratching at his back through his shirt. 

“Peter,” Jon gasps, working himself down too, all soft whimpers and lidded eyes as he gets himself off on Peter’s cock. “You’re so- Christ.” 

“Am I now?” The way Jon is moving seems to keep him tighter for longer. Peter could just sit back and let himself get slowly, lovingly coaxed into an orgasm. He could. “What am I, exactly? So big? So deep inside you?” Jon flushes, scowling, but he certainly doesn’t deny any of it. “So breaking your pretty little cunt open on my big, thick prick?”

“Good lord,” Jon mutters breathlessly, like said pretty little cunt isn’t busy desperately clenching around said big, thick prick, slick leaking down to coat Peter’s balls and thighs. “So insufferable.” 

“Poor thing.” Peter might be tempted to say more but Jon’s finally loosened enough to pry his cock back out of.

“W-Wait-”

“No,” Peter says, sheathing himself again, hard enough that Jon whines and claws at his shoulders again when he bottoms out. 

Peter isn’t going to last much longer, with such unrelenting pressure-pleasure around his prick. With Jon so clearly affected, trembling in his lap. Knocked breathless, knocked speechless by his cock. The thought alone is enough to make his dick twitch. That Peter can tame this caustic, surly creature by bouncing it in his lap.

“You look good like this, Jon,” Peter says. He noses against the side of the siren’s neck – breathes in, and Jon smells like salt water, the light tang of the ocean, hot metal – up to where his gills have pressed flat to his skin, made little slits that Peter can work open with his tongue. 

“Don’t, Peter-” 

One of Jon’s hands slides into his hair, fingers tangling through the strands. But not pulling him away, and Jon is still tight and throbbing around him, Jon is still arching his neck to the side, allowing more access, letting those gills spread apart enough for Peter’s tongue to slip into. To the hot, plush tissue below, flushed with Jon’s blood, the spiked frills fluttering against Peter’s lips, quiet stirs of air from however these things connect with Jon’s throat, his lungs. 

Peter wonders if he can’t Jon’s pry gills open far enough to fit the head of his cock inside them. See their thin flesh bulge around the intrusion of it. Bow outwards when he draws his hips back. Maybe the siren’s throat is even tighter than its cunt.

Or perhaps he’d rather just fuck Jon’s mean, pretty mouth. Stuff his prick down his throat that way and watch his come bubble out through these quivering gills. Peter tugs at their delicate form with his teeth, digs his tongue in deeper at the thought like he could already lick his own seed out.

“Please,” Jon gasps. The word buzzes in his throat, a pleasant vibration against Peter’s lips, around his tongue. 

Jon squirms in his lap, hips working like he’d be riding Peter if he could. It’s inspiring. Peter pulls off his neck so he can drink in the whole experience. Jon’s head tilting back, exertion flushing from his chest up along his neck. Spine arching as he drives himself futilely downward.

“So good,” Peter murmurs. “I bet Elias would love to see you like this, too.” 

The effect is rather instantaneous – almost insultingly so, if Peter’s honest. Jon moans, a shamelessly uninhibited sound, his body shivering in Peter’s lap. 

“You’d like that, wouldn’t you? Want Elias to watch me break you in for him, get you nice and open and positively dripping for his cock.” 

Little choked noises are the only answer Peter gets, the clenching of the siren’s cunt around his cock practically spasmodic.

“He could slide right inside you, all slicked up with my come, and I suppose you’d just let him add his to the mess, too.” 

If he times it just right, Peter finds, he can draw his cock back between the pulsing clutch of Jon’s muscles, pull out and fuck back in while the siren gasps, seeming close to tears. 

“If you stayed like this we could keep you full all the time, insatiable little whore that you are.” Peter’s sounding breathless now himself. “Decorating our laps, isn’t that what you said?” 

“Peter,” Jon whines. The air is kicked out of him with everything thrust of Peter’s cock. “Please, please-”

“How about we let Elias have a preview?” Jon groans, a sound that dies in its middle as the fog lifts and they’re both suddenly skewered by the Eye’s attention. “Go on, give him a nice show.” 

That’s all it takes, really, mildly irritating as Jon breathes out Elias’ name and clenches down hard, and wet, and throbbing, and strangely undulating around Peter’s cock. He feels that dull pang in his chest again and buries it in the sensation of rolling his hips up, chasing physical sensation until his orgasm is practically milked out of him, Jon solid and warm, shivering in his arms and tight around his prick. 

There’s nothing but bright white pleasure for a while. Jon bites at the side of his throat with thankfully blunted teeth, only the incisors sharp enough still to draw any blood and the wound throbs in time to the heady pulsing of his orgasm. At the peripheries is the scouring weight of Eyes – of Elias focused on the two of them. Jon’s arms are around his neck. Every breath is warm against his skin, Jon’s tongue a shock of wet heat lapping apologetically at the indented bruise his teeth left. 

His cock won’t stop twitching, caught up in the slick tight heat of the siren’s cunt. Even as both of them slowly come down, and Jon pulls off from the bend of his neck to hover his mouth above his own, letting their breathing comingle until Peter closes that distance, too, and relishes the sting of Jon drawing himself away, eventually.


End file.
